1. Field of the Invention
The present invention relates to a board connecting terminal and a connector using the same, which connector connects circuit boards orthogonally arranged, for example, in a motor vehicle.
2. Description of the Related Art
FIG. 18 shows a prior art connector disclosed in Japanese Patent Application Laid-open No. 10-302909. This connector consists of a female connector 122 openable-and-closable about a hinge 121 as a fulcrum and a male connector 123 inserted the female connector 122.
The female connector 122 consists of an upper and lower pair of housings 124 of synthetic resin and terminals 125 accommodated in each housing 124. The terminal 125 has an elastically contacting piece 125 on one side and an electric wire crimping portion (not shown) on the other side. The elastically contacting piece 125 projects from a rectangular opening 126 of the housing 124, and the electric wire crimping portion is crimped to an electric wire 127.
The male connector 123 consists of a housing 128 of synthetic resin and terminals 129 accommodated in the housing 128 in upper and lower layers. The terminal 129 has a tabular electrically contacting portion 129 and an electric wire crimping portion (not shown), and the electrically contacting portion 129 projects from an opening 130 each provided on both front and back sides of the housing 128.
The male housing 128 has tapered pushing portions 131 on the front end. The female housing 124 has, on the hinge side, tapered pushed portions 132 for the respective pushing portions 131.
On inserting the male connector 123 into the female connector 122 the tapered pushing portion 131 abuts the pushed portion 132, while closing the upper and lower housings 124. By this, the upper and lower elastically contacting pieces 125 are put into contact with the electrically contacting portions 129 elastically, and the electric wires 127,133 are mutually connected.
With respect to the above prior art connector 122, however, because the electric wire 127, as a circuit conductor, has to be connected to the terminal 125 by means of the crimping, the pressure welding, or the welding, many man-hours are required. Therefore, this connector has no degree of freedom of attaching or detaching the electric wire 127 to/from the terminal 125. The circuit (the terminal) 129 is connected to the connector 122 only in parallel (horizontal).
When both ends of the elastically contacting piece of the terminal 125 of the connector 122 are fixed in the opening 126 of the housing 124, the spring modulus of the elastically contacting piece becomes larger. Therefore, when a necessary displacement of the elastically contacting piece is not secured because of, for example, a dimension error of the terminal 125, a necessary contact pressure would not be obtained. When a projection of the elastically contacting piece is small because of a dimension error, the contact pressure for the mating terminal (the circuit conductor) 129 becomes small, thereby lowering reliability of the electrical connection.
In view of the foregoing, an object of the present invention is to provide a board connecting terminal and a connector using the terminal, which connector can be applied to circuit boards arranged in a crossing direction or an orthogonal direction to each other, can reduce time for the connection with the circuit conductors, can enhance the degree of freedom of attaching to or detaching from the circuit conductors, can easily secure a necessary contact pressure to the circuit conductors, and can securely connect both the circuit boards with an appropriate contact pressure.
In order to achieve the above object, as a first aspect of the present invention, a board connecting terminal comprises: a first elastic contact portion projecting arcuately or mountain-shapedly; a second elastic contact portion curved or inclined and extending in substantially the same direction as a projecting direction of the first elastic contact portion; and a middle baseplate portion being curved or straight and connecting the first elastic contact portion and the second elastic contact portion.
As a second aspect of the present invention, based on the first aspect, a short straight portion is formed at a free end of the first elastic contact portion.
As a third aspect of the present invention, based on the first aspect, in place of the second elastic contact portion, another elastic contact portion in substantially the same shape as the first elastic contact portion and is formed axial-symmetrically with the first elastic contact portion.
As a fourth aspect of the present invention, a connector, using the board connecting terminal having any one of the first to third aspects, to put the first elastic contact portion into contact with a first circuit board and put the second elastic contact portion into contact with a second circuit board comprises: a connector housing accommodating at least the first elastic contact portion of the board connecting terminal; and a supporting portion provided on the connector housing so as to slidably support the middle baseplate portion, wherein the free end of the first elastic contact portion abuts, or is fixed to the connector housing, and the board connecting terminal is longitudinally slidably supported by the supporting portion.
As a fifth aspect of the present invention, based on the fourth aspect with the board connecting terminal of the third aspect, a free end of the second elastic contact portion is slidably supported by the connector housing.
As a sixth aspect of the present invention, based on the fourth aspect, a stopping portion to abut the supporting portion is formed between the middle baseplate portion and the second elastic contact portion.
As a seventh aspect of the present invention, based on the fourth aspect, the connector housing consists of a pair of housings openable-and-closable through a hinge, and the first circuit board is inserted between the housings.
As an eighth aspect of the present invention, based on the fourth aspect, the connector housing has a board insertion hole in which the first elastic contact portion projects and an opening from which the second elastic contact portion projects.
As a ninth aspect of the present invention, based on the fourth aspect, the connector housing is provided with an engaging means to engage the second circuit board.
As a tenth aspect of the present invention, based on any one of the fourth to ninth aspects, at least two kinds of board connecting terminals having different respective lengths are provided, and the board connecting terminal having a longer length is put into contact with a third circuit board arranged behind the second circuit board.
According to the above-described structures of the present invention, the following advantages are provided.
(1) Because the first elastic contact portion is put into contact with one circuit board and the second elastic contact portion is put into contact with the other circuit board, both the crossed or orthogonal circuit boards can be securely and easily connected to each other with low cost. That is, because the crimping work of an electric wire and a terminal is unnecessary, connection time for the terminal and the circuit conductor of the circuit board is reduced, the degree of freedom of attaching/detaching the terminal to/from the circuit conductor, and assemblage and maintaining are made easier.
Because the second elastic contact portion extends in substantially the same direction the projecting direction of the first elastic contact portion, the first and second elastic contact portions are bent stably when the first elastic contact portion is pressed on one circuit board and the second elastic contact portion is pressed on the other circuit board. And, because the contact pressures of both the elastic contact portions against the circuit boards are smoothly balanced (equalized) through the middle baseplate portions, the elastic contact portions are put into contact with the respective circuit boards with equal and appropriate contact pressures, thereby improving reliability of the electrical connection.
(2) Because the straight portion on the free end of the first elastic contact portion abuts the connector housing and is secured, the terminal extends in a direction opposite to the free end, i.e. toward the second elastic contact portion, when the first elastic contact portion is pressed on one circuit board and bent. And, when the second elastic contact portion is pressed on the other circuit board and bent, the first elastic contact portion can securely receive the bending reaction force. Therefore, the contact pressures of the elastic contact portions are smoothly and securely adjusted.
(3) Because the first elastic contact portion and the second elastic contact portion are similarly shaped, the contact pressures of the elastic contact portions are easily equalized and accurately balanced, thereby further improving reliability of the electrical connection. And, because both the elastic contact portions are axial-symmetrically formed, the crossed or orthogonal circuit boards can be easily connected.
(4) Because the first elastic contact portion is put into contact with one circuit board and the second elastic contact portion is put into contact with the other circuit board, both the crossed or orthogonal circuit boards can be securely and easily connected each other with low cost. That is, because the crimping work of an electric wire and a terminal is unnecessary, connection time for the terminal and the circuit conductor of the circuit board is reduced, the degree of freedom of attaching/detaching the terminal to/from the circuit conductor, and assemblage and maintenancability are improved.
And, when the first elastic contact portion is pressed on one circuit board and the second elastic contact portion is pressed on the other circuit board, an unbalance of the contact pressures can be corrected by a movement of the terminal along the supporting portion, thereby improving reliability of the electrical connection.
(5) Because the free end on a side of the second elastic contact portion formed similarly to the first elastic contact portion is slidably supported by the connector housing, the second elastic contact portion bends around the free end as a fulcrum and smoothly moves (slides) along the supporting portion of the connector housing when the second elastic contact portion is pressed on the other circuit board. Therefore, when the contact pressures of the first elastic contact portion is small, the contact pressure of the first elastic contact portion is further securely revised.
(6) When the second elastic contact portion is put into initial contact with the other circuit board, the stopping portion of the terminal abuts the supporting portion of the connector housing and therefore the terminal does not move toward the first elastic contact portion. Therefore, because an insertion gap for one circuit board is secured on the side of the first elastic contact portion, the one circuit board can be smoothly inserted with a small force, thereby improving connecting workability of the circuit board.
(7) When the other circuit board is inserted between the pair of housings, both the housings are closed, the terminal turns in the closing direction integrally with the housing, and the second elastic contact portion is pressed on the other circuit board. Therefore, the contact between both the elastic contact portions and both the respective circuit boards is carried out simultaneously, thereby improving equalization of the contact pressures of the elastic contact portions.
(8) When one circuit board is inserted into the board insertion hole, the first elastic contact portion is put into contact with one circuit board elastically and the second elastic contact portion is put into contact with the other circuit board elastically from the opening. Therefore, the crossed or orthogonal circuit boards are securely and easily connected through both the elastic contact portions.
(9) Because the second elastic contact portion is put into contact with or is in a state near a contact with the other circuit board by engaging the connector housing with the other circuit board, the one circuit board can be easily inserted toward the first elastic contact portion.
(10) Because a power terminal and a signal terminal can be easily formed by at least changing the length of the middle baseplate portion, the cost for the terminal can be reduced.
The above and other objects and features of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings.